FIG. 7 shows an example of a conventional LED module. The LED module 900 illustrated in the figure includes leads 91A and 91B, an LED chip 92, and a case 93 and is configured as a so-called side-view type. The leads 91A and 91B each comprises a plate made of e.g. art alloy of Cu or Ni plated with Ag. The LED chip 92 is mounted on the lead 91A. The LED chip 92 is configured to emit e.g. blue light. The LED chip 92 and the lead 91B are connected to each other with a wire 95. The case 93 is made of e.g. white resin and surrounds the four sides of the LED chip 92. Portions of the leads 91A and 91B that are exposed from the case 93 serve as mounting terminals 91Aa and 91Ba. The space surrounded by the case 93 is filled with light-transmitting resin, not shown. The light-transmitting resin is made of e.g. a transparent resin mixed with a fluorescent substance. The fluorescent substance emits e.g. yellow light when excited by the light emitted from the LED chip 92. The blue light from the LED chip 92 and the yellow light from the fluorescent substance mix with each other, so that white light is emitted from the LED module 900.
One of the means for increasing the application of the LED module 900 is to configure the LED module to emit light of a plurality of colors, instead of a single color. For this purpose, it is necessary to provide a plurality of LED chips 92 that emit light of different wavelengths from each other. However, in the LED module 900 of a side-view type, the height (the dimension in the vertical direction in the figure) is often limited to a certain value. Thus, it is desirable to arrange the LED chips 92 as close to each other as possible. Further, when the LED chips 92 are too far away from each other, light of different colors cannot sufficiently mix with each other when all the LED chips 92 are turned on.
Patent Document: JP-A-2006-253551